A team of astronomers has found that neighbouring Andromeda galaxy (M31) and our own galaxy have a similar percentage of newborn stars based on mass
In the survey, the team looked at the NASA’s Hubble Space Telescope images of 2,753 young, blue star clusters in the neighbouring Andromeda galaxy (M31).
By nailing down what percentage of stars have a particular mass within a cluster, or the Initial Mass Function (IMF), scientists can better interpret the light from distant galaxies and understand the formation history of stars in our universe.
Daniel Weisz of the University of Washington in Seattle said that given the sheer volume of Hubble images, their study of the IMF would not have been possible without the help of citizen scientists.
Hubble’s bird’s-eye view of M31 allowed astronomers to compare the IMF among a larger-than-ever sampling of star clusters that are all at approximately the same distance from Earth, 2.5 million light-years.
To the researchers’ surprise, the IMF was very similar among all the clusters surveyed. Nature apparently cooks up stars like batches of cookies, with a consistent distribution from massive blue supergiant stars to small red dwarf stars.
It’s hard to imagine that the IMF is so uniform across our neighbouring galaxy given the complex physics of star formation, added Weisz.
The study appears in the Astrophysical Journal.